is a one-dimensional GeoGraphics primitive that represents the separation line between the halves of the Earth currently in daytime and nighttime.


represents the separation line between day and night for the specified date.


  • datespec can be specified as a DateObject or a string that resolves to a date.
  • A date without explicit time zone is assumed to use $TimeZone.


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Basic Examples  (2)

Display the current terminator as a line:

Show the terminator line on the summer solstice using red lines to denote the Arctic and Antarctic Circles:

Use a different projection:

Scope  (3)

DayNightTerminator[] gives a plot for the current date and time:

Using Now explicitly gives the same result:

Illustrate changes in the terminator at monthly intervals:

Specify dates in other formats:

Properties & Relations  (3)

The terminator line separates the day and night hemispheres:

Next lunar eclipse to a given date:

The night hemisphere coincides with the total phase area of the eclipse:

For a spherical model of the Earth, the terminator line is approximately a geo circle:

The true terminator and approximate terminator geo circle differ slightly when using an ellipsoidal model of the Earth:

Introduced in 2014